ABSTRACT
A preparation of antibody molecules that arises from several different clones of cells is called a polyclonal antibody. It is a mixture of antibody molecules that bind to different parts of the antigen and with different binding affinities. Antibody produced by single clone of cells is a monoclonal antibody; all the antibody molecules are identical and bind to the same antigenic site with identical binding affinities. Monoclonal antibodies can be generated in large amounts by creating a cell fusion between an antibody-producing cell and a myeloma cell. The cell fusion is called a hybridoma, which is both immortal and secretes the same specific antibody originally encoded by the B lymphocyte. Monoclonal antibodies produced using this technology are now common tools in research because of their very high specificity. In 1975, Milstein and Kohler discovered how monoclonal antibodies of almost any desired antigen specificity can be produced indefinitely and in large quantities.
